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Referral and warning signs
When to refer
Refer to Optometrist or Ophthalmologist/Eye Centre for refraction and prescription of corrective lenses. Refer children with suspected refractive error promptly to prevent amblyopia. Refer patients interested in contact lenses or refractive surgery.
Red flags
- Sudden change in vision.
- Eye pain.
- Double vision (diplopia).
- Vision loss not correctable with pinhole/refraction (suggests underlying pathology).
Signs and symptoms
- Blurred vision (at distance, near, or both).
- Eye strain (asthenopia).
- Headaches (especially after reading/close work).
- Squinting.
- Double vision (diplopia - less common with simple refractive error).
- Difficulty seeing at night.
- Myopia (Nearsightedness): Difficulty seeing distant objects clearly.
- Hyperopia (Farsightedness): Difficulty seeing near objects clearly (may also affect distance vision if severe or older age).
- Astigmatism: Blurred or distorted vision at all distances.
- Presbyopia (Age-related Farsightedness): Difficulty focusing on near objects, typically starting around age 40+.
Risk factors
- Family history.
- Ethnicity.
- Certain environmental factors (prolonged close work potentially linked to myopia progression).
- Age (presbyopia is age-related).
Diagnosis
Clinical assessment
History of blurred vision or associated symptoms (eye strain, headaches). Visual acuity testing (distance and near) confirms reduced vision correctable with pinhole.
Investigations
- Visual Acuity Testing (Snellen chart for distance, reading chart for near).
- Pinhole Test: If vision improves with pinhole, suggests refractive error.
- Refraction: Objective (Retinoscopy or Autorefractor) and Subjective testing to determine the specific type and power of refractive error. Performed by Optometrist or Ophthalmologist.
- Ocular health assessment (slit lamp, fundoscopy) to rule out other causes of blurred vision.
Diagnostic criteria
Reduced visual acuity correctable to normal or near-normal with appropriate lenses (glasses/contacts) during refraction.
Management
Pharmacological treatment
- No pharmacological treatment for refractive error itself.
Monitoring
Regular eye examinations and update of prescription as needed (e.g., every 1-2 years, or sooner if vision changes). Monitor children for progression (especially myopia).
Complications
- Uncorrected refractive error: Poor school/work performance, eye strain, headaches, amblyopia (if significant error in childhood uncorrected).
- High myopia: Increased risk of retinal detachment, glaucoma, myopic maculopathy.
- Contact lens complications: Infection (keratitis), dry eye, allergy.
Prevention
- Currently no proven methods to prevent onset of most refractive errors.
- Some evidence suggests increased outdoor time may slow myopia progression in children.
- Regular eye exams for early detection.
Patient education
- Explanation of the specific refractive error (myopia, hyperopia, etc.).
- How corrective lenses work.
- Importance of wearing correction as prescribed.
- Proper care for glasses/contact lenses.
- Need for regular eye check-ups.
- Symptoms indicating need for review (worsening vision, eye strain).
Uganda-specific notes
Uncorrected refractive error is a major cause of visual impairment. Access to refraction services and affordable spectacles is limited, especially in rural areas. School vision screening programs are important.
Optical Correction
- Spectacles (Glasses): Most common, safe, and effective method. Lenses prescribed based on refraction result (spherical power for myopia/hyperopia, cylindrical power and axis for astigmatism, add power for presbyopia).
- Contact Lenses: Alternative to spectacles. Require proper fitting, hygiene, and care.
- Refractive Surgery (LASIK, PRK, etc.): Surgical procedures to reshape the cornea. Specialist procedures with specific indications/contraindications.
References
- Uganda Clinical Guidelines (UCG) 2023
Chapter 20, Section 20.2.4